Experts warn N. Sumatra lies on shaky ground

Apriadi Gunawan, The Jakarta Post, Medan

Located in a geologically active area, North Sumatra is at risk of major earthquakes, according to several experts.

The experts were speaking at a national seminar in Medan on earthquakes and tsunami, in the context of building construction, regulations and public attitudes. The seminar was hosted by the North Sumatra regional council and the Medan Meteorology and Geophysics Agency (BMG).

Dradjat Hoedajanto, a specialist at the Bandung Institute of Technology, said the threat of earthquakes in North Sumatra was real. He said there was the potential for a major quake measuring up to 7.6 on the Richter scale to hit the area. He said residents could expect such a major earthquake within the next 10 years to 20 years.

Earlier quakes in Aceh and Nias resulted from the subduction of the Sumatra Trench, which Dradjat said would not affect North Sumatra.

"North Sumatra is not at risk from the quake threat posed by the Sumatra Trench, but attention should be given to yet another source of danger, the Sumatra Fault, which has the potential to produce quakes measuring over 7.6 in magnitude" Dradjat told hundreds of seminar participants.

Omer Aydan, a scientist with the Department of Marine Civil Engineering at Tokai University in Japan, said he was convinced a major earthquake would strike North Sumatra following the Aceh and Nias quakes, but not in the short term.

According to BMG data, there are at least 16 potential epicenters for major quakes in North Sumatra, eight of which in the waters near Nias. An earthquake measuring 8.7 on the Richter scale rocked Nias on March 28, claiming hundreds of lives.

Dradjat said now was the time for the government and the people of North Sumatra to begin preparing for possible earthquake disasters. He suggested the government pay particular attention to putting into place the facilities and infrastructure necessary to respond to any natural disaster.

In the view of Dradjat, who is also chairman of the Professional Certification Program at the Indonesian Construction Engineers Association, such preparations are vital, as proven by the experience of Aceh and Nias, where countless buildings were topped by the quakes, leading to heavy death tolls.

His field survey found that most of the buildings topped in the quakes were constructed using substandard materials. Dradjat warned construction companies about cutting corners when it came to building materials.

Masturiyono from the BMG told residents not to panic about the quake threat, saying there were no instruments that could determine exactly where and when an earthquake would hit.